As the rate of adoption of cellular or mobile telephone use continues to increase, there is a need to provide greater wireless coverage of service areas. One method of increasing that coverage, while also providing additional benefits, is the installation of in-building solutions for customers. In-building solutions feature a wireless adjunct unit in communication with a Private Branch Exchange (“PBX”) within a customer's building. While the PBX services the customer's general desk top telephone needs, the wireless adjunct unit acts as an extension of a service provider's mobile telephone network that services the wireless needs of the service provider's customers within the building.
Incoming telephone calls to the PBX may be routed to the desktop telephone and a user's mobile unit, either simultaneously or in some predefined sequential order. When a user goes off-hook on either the mobile unit or the desktop phone, the call is setup and connected through the off-hook device, and any ongoing attempt to setup a call with the non-responding device is terminated. Thus, a user may receive an inbound PBX based call at either the traditional desktop telephone or at her mobile phone. Similarly, outbound calls from the user's mobile unit may be received by the wireless adjunct unit and routed through the building PBX to a destination number. Unfortunately, only users who have access to the PBX may utilize the in-building solution to place outbound calls or to receive inbound calls. Users who are guests within the building are at the mercy of the quality of coverage provided by external base station sites; often, poor coverage from such sites within the building is a large factor in the decision to install the in-building solution.
The wireless adjunct unit may provide base station functionality by interfacing to one or more antennae or repeater sites hardwired to the wireless adjunct unit placed throughout the building. Installation of such a hardwired system can be expensive and time consuming, as wiring needs to be installed or retrofitted throughout the building in order to provide signaling between the antennae or repeater sites and the PBX. In addition, the interfaces between the PBX and the adjunct unit and between the adjunct unit and the repeater sites are generally proprietary to the manufacturer of the equipment, thus limiting customer choice in purchasing and installing in-building solutions.
Embodiments of the present invention are directed to overcoming one or more of the problems identified above.